What are the signs and symptoms of Attention Deficit Hyperactivity Disorder (ADHD)?

Signs of Attention Deficit Disorder

ADHD is characterized by three core symptom domains: inattention, hyperactivity, and impulsivity, which must cause functional impairment in at least two settings (home, school, work, or social environments) to meet diagnostic criteria. 1

Core Symptom Categories

Inattentive Symptoms

The following signs indicate problems with sustained attention and organization: 1

• Easily distracted and fails to pay close attention to details 2
• Difficulty sustaining attention during tasks or play activities 1
• Does not seem to listen when spoken to directly 1
• Fails to follow through on instructions and does not complete tasks 2
• Difficulty organizing tasks, activities, materials, and time 1
• Avoids or dislikes tasks requiring sustained mental effort 1
• Frequently loses necessary items (school materials, keys, wallet, phone) 1
• Forgetful in daily activities 1

Hyperactive/Impulsive Symptoms

The following signs indicate problems with motor control and impulse regulation: 1

• Fidgets with hands or feet or squirms in seat 1
• Leaves seat in situations where remaining seated is expected 1
• Runs or climbs excessively in inappropriate situations (in adolescents/adults, may manifest as restlessness) 2
• Unable to engage quietly in leisure activities 1
• "On the go" or acts as if "driven by a motor" 1
• Talks excessively 1
• Blurts out answers before questions are completed 1
• Difficulty waiting their turn 1
• Interrupts or intrudes on others frequently 2

Diagnostic Requirements

To establish an ADHD diagnosis, specific criteria must be met: 1, 3

• At least 6 symptoms from either the inattentive or hyperactive/impulsive category (or both) must be present 3
• Symptoms must persist for at least 6 months 3
• Symptoms must have been present before age 12 1
• Impairment must occur in at least 2 settings (e.g., home and school, work and social situations) 1
• Clear evidence of functional impairment in social, academic, or occupational functioning 1

Age-Specific Presentations

Preschool Children (Ages 4-5)

Diagnosis is more challenging in this age group due to developmental variability: 1

• Extreme hyperactivity that exceeds typical preschool activity levels 1
• Inability to sit during structured activities like meals or story time 1
• Aggressive or impulsive behaviors that disrupt peer interactions 1
• Difficulty following simple instructions consistently 1

School-Age Children (Ages 6-11)

Symptoms become more apparent in structured settings: 1

• Academic underachievement despite adequate intelligence 4
• Not completing homework or classwork 1
• Disruptive classroom behavior 1
• Difficulty with peer relationships 4
• Low self-esteem related to repeated failures 4

Adolescents (Ages 12-18)

Presentation often shifts with maturation: 1

• Overt hyperactivity declines, but internal restlessness persists 1
• Inattentive symptoms become more prominent and problematic 1
• Disorganization of materials, time, and long-term planning 1
• Academic difficulties intensify with increased demands 1
• Risk-taking behaviors may emerge 1

Important caveat: Adolescents often minimize their own symptoms when self-reporting, making collateral information from teachers and parents essential. 1

Adults

Adult presentation differs from childhood manifestations: 2, 5

• Predominantly inattentive symptoms rather than hyperactivity 6
• Chronic disorganization affecting work and home life 2
• Difficulty completing tasks and meeting deadlines 2
• Restlessness rather than overt hyperactivity 5
• Impulsivity in decision-making 5
• Emotional dysregulation and stress intolerance 7

Associated Features (Not Diagnostic but Common)

Additional symptoms frequently accompany ADHD: 4

• Overemotionality or overreactivity to situations 4
• Interpersonal difficulties in relationships 4
• Low frustration tolerance 4
• Mood lability 7

Critical Diagnostic Considerations

Information Sources

Diagnosis requires information from multiple observers across different settings, not just parental or self-report: 1

• Parent/guardian reports using standardized rating scales 1
• Teacher reports from at least 2 teachers (for adolescents, include coaches or activity leaders) 1
• Direct observation when possible 1
• Collateral information from other adults who interact with the child 2

Common Pitfalls to Avoid

Rule out alternative explanations before diagnosing ADHD: 1

• Sleep disorders (especially sleep apnea) can mimic inattention 1
• Anxiety and depression present with concentration difficulties 1
• Learning disabilities may appear as inattention in specific subjects 1
• Substance use (particularly marijuana in adolescents) mimics ADHD symptoms 1
• Trauma and toxic stress can produce ADHD-like behaviors 1
• Autism spectrum disorders may include attention difficulties 1

Comorbidity Screening

Screen for comorbid conditions in every ADHD evaluation, as the majority of children with ADHD meet criteria for another disorder: 1

• Oppositional defiant disorder and conduct disorder (more common in boys) 1
• Anxiety and depression (more common in girls) 1
• Learning and language disorders 1
• Tic disorders 1
• Substance use disorders (in adolescents and adults) 1

Feigned Symptoms

Be alert to symptom exaggeration in adolescents and adults, particularly those seeking stimulant medications for performance enhancement rather than treatment. 1

Genetic and Familial Patterns

ADHD has heritability rates of 70-80%, making it one of the most heritable neuropsychiatric conditions: 3

• Positive family history significantly increases risk 3
• Symptom patterns may vary between generations (e.g., parent had combined type, child has predominantly inattentive type) 3
• Parents with ADHD may need additional support managing their child's treatment 3